Rice cleaning machine



Sept. 19, 1939. K. MORI RICE CLEANING MACHINE Filed Dec. 16, 1957 Patented Sept. 19, 1939 UNITED STATES PATENT OFFICE RICE CLEANING MACHINE Kanjiro M6ri, Shigaken, Japan Application December 16, 1937, Serial No. 180,234

1 Claim.

The present invention relates to an improvement in the rice-cleaning machine in which a revolving drum is arranged within a hexagonal wire-gauze casing with a number of radiating plates. A current of cold compressed air is passed through longitudinal openings disposed on the trailing side of projections which are also provided on said revolving drum so as to cool the rice grains contained in the casing during the cleaning operation. The cooling of the wiregauze casing may be simultaneously effected by the compressed air as well as with the radiating plates so that the clogging of the meshes of the wire-gauze with the bran may be completely avoided. The object of the invention is to prevent the degeneration of the cleaned rice due to the heat evolved in the cleaning.

In the rice-cleaning machines hitherto used in which the bran is removed by the friction of raw grains between themselves in a revolving casing there is danger of the cleaned rice being deteriorated by heating. In order to overcome this difficulty it is usual to mix the raw grains with sand for cleaning. In this case cleaning may indeed be effected in a comparatively short time, as the bran can be easily removed by the sand, but the cleaned rice is liable to being unduly worn out, so that the yield comes to be considerably reduced.

In the present invention rice-grains to be cleaned can be kept at ordinary temperatures, as they are cooled by air throughout the treatment, and consequently the degeneration of the cleaned rice can be effectively avoided. The loss due to the wearing out of the grains may be also removed, no sand being used in this invention.

The longitudinal openings formed each along the base of projections on the periphery of the revolving drum are located on the trailing side to the direction of revolution of said drum, i. e., where the grains are loosely amassed, so that intimate contact of air and the grains can be insured, radiation of heat being effected rapidly.

The invention will now be fully explained in reference to the accompanying drawing, in which Fig. l is a partial sectional front view of the rice-cleaning machine according to the present invention and Fig. 2 is an enlarged sectional elevation of same on the line A-B of Fig. 1.

On the frame horizontally mounted is a hollow shaft 2 which communicates at one end with the air-outlet of the blower 3. The pulleys i, 5 are keyed to the hollow shaft 2, the pulley l being connected by a belt with a pulley on the driving shaft and the pulley 5 by a belt 1 with the pulley 6 on the shaft of the blower.

To the other end of the shaft 2 are secured a spiral conveyer 8 and a revolving drum 9, which are journaled in a case l2 provided on its upper part with a hopper l0 fitted with a butterfly valve II. The raw rice-grains charged through the hopper l0 into the case l2 are fed into the hexagonal wire-gauze casing by the conveyer 8.

The revolving drum 9 is provided on its diametrically opposite periphery with a pair of projections l3, running parallel with the axis of said drum and extending over the whole length of same. It is further provided with a pair of longitudinal openings l4 formed each along the base of said projections on the trailing side to the direction of revolution. The drum is axially mounted on the shaft 2 and held in position by a nut I5. The portion of the hollow shaft which is found in the annular space between said shaft and drum is fitted out with a number of airoutlets II.

The revolving drum 9 is co-axially enclosed in the wire-gauze casing l8, hexagonal in section, which is surrounded with a plurality of radiating plates Ill. The casing and radiating plates are divided into two halves. Each half of the radiating plate has flanges 20 secured to its upper and lower ends respectively. The elongated ends of two halves of the casing are held between the flanges of the two halves of the radiating plate and secured in position by means of bolt and nut 2| so as to form one body.

The flanges of the terminal radiating plates are secured respectively to the side-plates 22, 23 with a hexagonal opening corresponding in size with the section of the Wire-gauze casing, said side-plate being fixed by bolt and nut 25 to the lateral walls of the case 24 forming in its lower portion a hopper 26. The case 24 is provided on its leftside-wall with a short cylindrical grain-outlet 21 with a cover-plate 28 fitted with a hinge 29 which is closed by a spring 30 attached to the upper part of said outlet.

On transmitting the revolution of the driving shaft to the hollow shaft 2 the blower is started and compressed air is forced out of the longitudinal openings M of the revolving drum through the outlets 11. Now the valve l l is suitably adjusted and raw rice-grains are charged into the hopper Ill, when they are fed by the spiral conveyer 8 into the wire-gauze casing and pressed against the inner surface of said casing by the projection I3 of the revolving drum. After cooling the grains the compressed air passes through the wire-gauze and escapes out of the hopper 26. The clogging of the meshes of the Wire-gauze with the bran is avoided, as the air is constantly passing through and cooling the wire-gauze during the treatment. The cleaned rice-grains are finally discharged through the grain-outlet by opening the cover-plate 28 against the spring 30.

What I claim is:

A rice cleaning machine comprising a hollow revolving shaft, a drum secured to said shaft, a

fixed hexagonal wire-gauze casing enveloping said drum, a plurality of projections extending parallel with the axis of said drum and over the whole length of same, said drum being provided with longitudinal openings on the trailing side of said projections, said hollow shaft having openings communicating with said drum and means for forcing compressed air through the hollow shaft into the drum and through the longitudinal openings into the Wire-gauze casing.

KANJIRO MORI. 

